The battle between Gov. Cuomo and Mayor Bloomberg over funding of the 9/11 Museum has entered its 10th month with no resolution in sight, despite optimistic statements from both sides just a couple of weeks ago that a deal was near.

In the meantime, work on the historic project has ground to a virtual halt.

Thousands of visitors from around the world who swarm to the haunting 9/11 memorial every day were supposed to be able to visit the accompanying museum starting in September. That opening has been pushed back indefinitely.

One insider said questions about whether the Port Authority or the museum foundation should be responsible for an estimated $150 million in infrastructure costs has narrowed to as little as $5 million that’s still in dispute.

“It’s a joke,” said the insider. “You’re dealing with $11 billion in construction [at the World Trade Center site], and they can’t get past this $5 million?”

Other larger numbers have also been tossed around. But they appear not to be major stumbling blocks.

“We’re down to a few things, a very small amount of money where we disagree,” the mayor announced on June 6.

The Post reported last week that Cuomo is holding the museum’s funding hostage out of distress that his dad, former Gov. Mario Cuomo, was treated shabbily at last year’s 10th anniversary Ground Zero ceremony.

The event was overseen by the city.

Those watching from the sidelines say whatever the reasons for the fracture, both the mayor and the governor are hurting their reputations by not coming to a speedy settlement.

“Everyone is going to have egg on their face,” said one source with ties to the trade center. “This thing is being delayed a year. For what?”

More worrisome is the possible fallout in Washington, where both Bloomberg and Cuomo have made strong pitches for $20 million a year in federal aid to help cover annual operating costs, estimated at $60 million, once the museum opens.

“I think we have the money from the federal government, but they’ve got to take it away from someplace else,” the mayor said on Friday. “So that’s the issue. Where do you find the money?”